Organic light-emitting device

Abstract

An organic light emitting device includes: a first electrode; a second electrode facing the first electrode; m emission units stacked between the first electrode and the second electrode; and m-1 charge generating layer(s) between the two adjacent emission units from among the m emission units, m-1 charge generating layer(s) including m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s), wherein m is an integer of 2 or greater, a maximum emission wavelength of light emitted from at least one of the m emission units differs from that of light emitted from at least one of the other emission units, at least one of the m-1 n-type charge generating layer(s) includes a metal-containing material and an electron transporting metal-non-containing material.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2016-0029093, filed on Mar. 10, 2016, in the Korean Intellectual Property Office, the entire content of which is incorporated herein by reference.

BACKGROUND

1. Field

One or more aspects of embodiments of the present disclosure relate to an organic light-emitting device.

2. Description of the Related Art

Organic light emitting devices are self-emission devices that have wide viewing angles, high contrast ratios, short response times, and excellent brightness, driving voltage, and response speed characteristics, and can produce full-color images.

An organic light-emitting device may include a first electrode on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode, which are sequentially positioned on the first electrode. Holes provided from, for example, the first electrode may move toward the emission layer through the hole transport region, and electrons provided from, for example, the second electrode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, may then recombine in the emission layer to produce excitons. These excitons transition from an excited state to a ground state, thereby generating light.

SUMMARY

One or more aspects of embodiments of the present disclosure are directed toward an organic light-emitting device having low driving voltage, high efficiency, and long lifespan.

Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

According to one or more embodiments, an organic light-emitting device includes a first electrode;

a second electrode facing the first electrode;

m emission units stacked between the first electrode and the second electrode; and

m-1 charge generating layer(s) between each of the two adjacent emission units from among the m emission units, the m-1 charge generating layer(s) including m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s),

wherein the m is an integer of 2 or greater,

a maximum emission wavelength of light emitted from at least one of the m emission units differs from that of light emitted from at least one of the other emission units,

at least one of the m-1 n-type charge generating layer(s) includes a metal-containing material and an electron transporting metal-non-containing material,

wherein the metal-containing material is selected from a metal, a metal complex, and combinations thereof,

the metal is selected from a rare-earth metal, a transition metal, a late transition metal, and combinations thereof, and

the metal complex is selected from an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, and combinations thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment;

FIG. 2 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment;

FIG. 3 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment;

FIG. 4 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment;

FIG. 5 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment; and

FIG. 6 is a schematic cross-sectional view illustrating an organic light-emitting device according to an embodiment.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the drawings, to explain aspects of the present description. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. Expressions such as "at least one of," "one of," and "selected from," when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Further, the use of "may" when describing embodiments of the present invention refers to "one or more embodiments of the present invention."

According to an embodiment of the present disclosure, an organic light-emitting device may include a first electrode;

a second electrode facing the first electrode;

m emission units stacked between the first electrode and the second electrode; and

m-1 charge generating layer(s) between each of the two adjacent emission units from among the m emission units, the m-1 charge generating layer(s) including m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s),

wherein m may be an integer of 2 or greater,

a maximum emission wavelength of light emitted from at least one of the m emission units may differ from that of light emitted from at least one of the other emission units,

at least one of the m-1 n-type charge generating layer(s) may include a metal-containing material and an electron transporting metal-non-containing material,

the metal-containing material may include a metal, a metal complex, or a combination thereof,

the metal may include a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and

the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof.

FIG. 1 illustrates a schematic view of an organic light-emitting device 10 according to an embodiment of the present disclosure. As shown in FIG. 1, an organic light-emitting device 10 according to an embodiment may include a first electrode 110; a second electrode 190 facing the first electrode; m emission units 153 stacked between the first electrode 110 and the second electrode 120; and m-1 charge generating layer(s) 155 between each of the two adjacent emission units 153 from among the m emission units 153, the m-1 charge generating layer(s) including m-1 n-type charge generating layer(s) 155' and m-1 p-type charge generating layer(s) 155'' (e.g., each charge generating layer 155 may include an n-type charge generating layer 155' and a p-type charge generating layer 155'').

The "emission unit" as used herein is not particularly limited and may be any suitable emission unit capable of emission. In some embodiments, the emission unit may include at least one emission layer. In some embodiments, the emission unit may further include an organic layer, in addition to an emission layer.

The organic light-emitting device 10 may include m stacked emission units 153, wherein m may be an integer of 2 or greater. m, which denotes the number of emission units, may be any suitable integer, and the upper limit of the number of emission units is not particularly limited. In some embodiments, the organic light-emitting device may include 2, 3, 4, or 5 emission units.

A maximum emission wavelength of light emitted from at least one of the m emission units may differ from that of light emitted from at least one of the other emission units. In some embodiments, in an organic light-emitting device that includes a first emission unit and a second emission unit that are stacked together, the maximum emission wavelength of light emitted from the first emission unit may differ from that of light emitted from the second emission unit. In this case, an emission layer of the first emission unit and that of the second emission unit may each independently include i) a single-layered structure including a single layer that includes a single material, ii) a single-layered structure including a single layer that includes a plurality of different materials, or iii) a multi-layered structure having a plurality of layers that include a plurality of different materials. Accordingly, light emitted from the first emission unit or the second emission unit may be single color light or mixed color light. In some embodiments, in an organic light-emitting device that includes a first emission unit, a second emission unit, and a third emission unit that are stacked together, the maximum emission wavelength of light emitted from the first emission unit may be the same as that of light emitted from the second emission unit, whereas the maximum emission wavelength of light emitted from the third emission unit may differ from that of light emitted from the first and second emission units. In some embodiments, the maximum emission wavelength of light emitted from the first emission unit, the maximum emission wavelength of light emitted from the second emission unit, and the maximum emission wavelength of light emitted from the third emission unit may differ from one another.

The organic light-emitting device 10 may include the charge generating layer 155 between the two adjacent emission units 153 from among the m emission units 153. Here, the term "adjacent" as used herein may refer to an arrangement of two layers positioned closest to each other. In some embodiments, the term "two adjacent emission units" may refer to an arrangement of two emission units disposed closest to each other from among a plurality of emission units. For example, the term "adjacent" may refer to an arrangement of two layers that, in some embodiments, may physically contact each other, and in other embodiments, may have another layer disposed therebetween. In some embodiments, an emission unit adjacent to a second electrode may refer to an emission unit disposed closest to the second electrode from among a plurality of emission units. In some embodiments, the second electrode may physically contact the emission unit, or additional layers other than the emission units may be present between the second electrode and the emission unit. In some embodiments, an electron transport layer may be between the second electrode and the emission unit. A charge generating layer may be between two adjacent emission units.

The charge generating layer may function as a cathode for one of the two adjacent emission units by generating electrons and as an anode for the other emission unit by generating holes. The charge generating layer may separate adjacent emission units, while not being directed connected to an electrode. In some embodiments, an organic light-emitting device including m emission units may include m-1 charge generating layer(s).

The charge generating layer 155 may include the n-type charge generating layer 155' and the p-type charge generating layer 155''. In some embodiments, the n-type charge generating layer 155' and the p-type charge generating layer 155'' may directly contact each other so as to form an NP junction (e.g., a P-N junction). Due to the NP junction, electrons and holes may be concurrently or simultaneously generated between the n-type charge generating layer 155' and the p-type charge generating layer 155''. The generated electrons may be transferred to one emission unit of the two adjacent emission units through the n-type charge generating layer 155'. The generated holes may be transferred to another emission unit of the two adjacent emission units through the p-type charge generating layer 155''. In addition, since the charge generating layers 155 may each include one n-type charge generating layer 155' and one p-type charge generating layer 155'', the organic light-emitting device 10 that includes m-1 charge generating layer(s) 155 may include m-1 n-type charge generating layer(s) 155' and m-1 p-type charge generating layer(s) 155''.

The term "n-type" as used herein may refer to n-type semiconductor properties, for example, properties capable of injection and transport of electrons. The term "p-type" as used herein may refer to p-type semiconductor properties, for example, properties capable of injection and transport of holes.

At least one of the m-1 n-type charge generating layer(s) may include a metal-containing material and an electron transporting metal-non-containing material (e.g., electron transporting material that does not include metal).

The metal-containing material may include a metal, a metal complex, or a combination thereof.

According to an embodiment, when at least one of the m-1 n-type charge generating layer(s) includes a metal as the metal-containing material, the metal may include a rare-earth metal, a transition metal, a late transition metal, or a combination thereof. In some embodiments, when at least one of the m-1 n-type charge generating layer(s) includes a metal as the metal-containing material, the metal may be selected from lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). According to an embodiment, when at least one of the m-1 n-type charge generating layer(s) includes a metal as the metal-containing material, the metal may be Yb, but embodiments are not limited thereto.

In one or more embodiments, when at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof. In some embodiments, when at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, a metal of the metal complex may be selected from lithium (Li), aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), zinc (Zn), and copper (Cu). According to an embodiment, when at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, the metal complex may be a Li complex or an Al complex, but embodiments are not limited thereto.

When at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, the metal complex may include at least one organic ligand selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxy benzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene. In some embodiments, when at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, the metal complex may include at least one selected from a substituted or unsubstituted hydroxyquinoline and a substituted or unsubstituted hydroxyphenyl benzothiazole, but embodiments are not limited thereto.

In some embodiments, when at least one of the m-1 n-type charge generating layer(s) includes a metal complex as the metal-containing material, the metal complex may be a lithium quinolate (Liq) and/or an aluminum quinolate (Alq.sub.3).

In some embodiments, a lowest unoccupied molecular orbital (LUMO) energy level of the electron transporting metal-non-containing material may be about -4.0 electron volts (eV) or greater. In some embodiments, a LUMO energy level of the electron transporting metal-non-containing material may be about -3.8 eV or greater. In some embodiments, a LUMO energy level of the electron transporting metal-non-containing material may be about -3.5 eV or greater.

Since an organic compound having a LUMO energy level of about -4.0 eV or greater has a slight difference in LUMO energy level with peripheral layers, the organic compound may efficiently (or suitably) transfer electrons generated in the n-type charge generating layer to the peripheral layers.

In one or more embodiments, the electron transporting metal-non-containing material may be an organic compound including at least one .pi. electron-depleted nitrogen-containing ring.

The term ".pi. electron-depleted nitrogen-containing ring" as used herein may refer to a C.sub.1-C.sub.60 heterocyclic group having at least one *--N.dbd.*' moiety as a ring-forming moiety.

For example, the ".pi. electron-depleted nitrogen-containing ring" may be i) a 5-membered to 7-membered heteromonocyclic group having at least one *--N.dbd.*' moiety, ii) a heteropolycyclic group in which two or more 5-membered to 7-membered heteromonocyclic groups each having at least one *--N.dbd.*' moiety are condensed (e.g., fused), and/or iii) a heteropolycyclic group in which at least one 5-membered to 7-membered heteromonocyclic group having at least one *--N.dbd.*' moiety is condensed with at least one C.sub.5-C.sub.60 carbocyclic group.

In some embodiments, the electron transporting metal-non-containing material may be an organic compound including at least one selected from an imidazole ring, a pyrazole ring, a thiazole ring, an isothiazole ring, an oxazole ring, an isoxazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, an indazole ring, a purine ring, a quinoline ring, an isoquinoline ring, a benzoquinoline ring, a phthalazine ring, a naphthyridine ring, a quinoxaline ring, a quinazoline ring, a cinnoline ring, a phenanthridine ring, an acridine ring, a phenanthroline ring, a phenazine ring, a benzoimidazole ring, an iso-benzothiazole ring, a benzoxazole ring, an isobenzoxazole ring, a triazole ring, a tetrazole ring, an oxadiazole ring, a triazine ring, a thiadiazole ring, an imidazopyridine ring, an imidazopyrimidine ring, and indenoquinoline ring. In some embodiments, the electron transporting metal-non-containing material may be an organic compound including at least one selected from a phenanthroline ring, an imidazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring.

According to an embodiment, the electron transporting metal-non-containing material may be represented by Formula 1: [Ar.sub.1].sub.c1-[(L.sub.1).sub.a1-R.sub.1].sub.b1, Formula 1

wherein, in Formula 1,

Ar.sub.1 may be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

c1 may be 1, 2, or 3,

when c1 is 2 or greater, a plurality of Ar.sub.1(s) may be identical to or different from each other, and the plurality of Ar.sub.1(s) may be connected to a respective one another via a single bond,

L.sub.1 may be selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 arylene group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

a1 may be an integer selected from 0 to 5,

when a1 is 0, *-(L.sub.1).sub.a1-*' may be a single bond, and when a1 is 2 or greater, a plurality of L.sub.1(s) may be identical to or different from each other,

R.sub.1 may be selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.1)(Q.sub.2)(Q.sub.3), --C(.dbd.O)(Q.sub.1), --S(.dbd.O).sub.2(Q.sub.1), and --P(.dbd.O)(Q.sub.1)(Q.sub.2),

wherein Q.sub.1 to Q.sub.3 may be each independently a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group,

b1 may be an integer selected from 1 to 5, and

when b1 is 2 or greater, a plurality of [(L.sub.1).sub.a1-R.sub.1](s) may be identical to or different from each other.

In some embodiments, in Formula 1,

Ar.sub.1 may be selected from the group consisting of:

a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzoimidazole group, an iso-benzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, indenoquinoline group, a pyridoquinazoline group, and a benzoimidazoquinazoline group; and

a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzoimidazole group, an iso-benzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, indenoquinoline group, a pyridoquinazoline group, and a benzoimidazoquinazoline group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

L.sub.1 may be selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, and

R.sub.1 may be selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, and a pyridonaphthyridinyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, and a pyridonaphthyridinyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group; and

--S(.dbd.O).sub.2(Q.sub.1) and --P(.dbd.O)(Q.sub.1)(Q.sub.2),

wherein Q.sub.1, Q.sub.2, and Q.sub.31 to Q.sub.33 may be each independently a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.

According to an embodiment, the electron transporting metal-non-containing material may be selected from Compounds 1 to 21, but embodiments are not limited thereto:

##STR00001## ##STR00002## ##STR00003## ##STR00004## ##STR00005##

According to an embodiment, when an n-type charge generating layer, which includes the metal-containing material and the electron transporting metal-non-containing material, includes the metal as the metal-containing material, a weight ratio of the metal to the electron transporting metal-non-containing material may be in a range of about 0.01:100 to about 15:100. In some embodiments, a weight ratio of the metal to the electron transporting metal-non-containing material may be in a range of about 1:100 to about 5:100, but embodiments are not limited thereto.

According to an embodiment, when an n-type charge generating layer, which includes the metal-containing material and the electron transporting metal-non-containing material, includes the metal complex as the metal-containing material, a weight ratio of the metal complex to the electron transporting metal-non-containing material may be in a range of about 1:100 to about 100:1. In some embodiments, a weight ratio of the metal complex to the electron transporting metal-non-containing material may be in a range of about 1:50 to about 50:1. In some embodiments, a weight ratio of the metal complex to the electron transporting metal-non-containing material may be in a range of about 1:25 to about 25:1. In some embodiments, a weight ratio of the metal complex to the electron transporting metal-non-containing material may be in a range of about 3:7 to about 7:3, but embodiments are not limited thereto.

The p-type charge generating layer may substantially smoothly generate holes between the p-type charge generating layer and the n-type charge generating layer, and a material for the p-type charge generating layer is not particularly limited, and may be any suitable material capable of smoothly transferring generated holes to an adjacent emission unit. In some embodiments, the p-type charge generating layer may include only an organic compound. In some embodiments, the p-type charge generating layer may further include a metal oxide. In some embodiments, the p-type charge generating layer may further include a p-type dopant.

According to an embodiment, the p-type charge generating layer may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments are not limited thereto.

In some embodiments, a material for the p-type charge generating layer may include at least one selected from the group consisting of:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and/or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide and/or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

compounds represented by Formula 221, but embodiments are not limited thereto:

##STR00006##

wherein, in Formula 221,

R.sub.221 to R.sub.223 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, provided that at least one selected from R.sub.221 to R.sub.223 may include at least one substituent selected from a cyano group, --F, --Cl, --Br, --I, a C.sub.1-C.sub.20 alkyl group substituted with --F, a C.sub.1-C.sub.20 alkyl group substituted with --Cl, a C.sub.1-C.sub.20 alkyl group substituted with --Br, and a C.sub.1-C.sub.20 alkyl group substituted with --I.

According to an embodiment, the thickness of the n-type charge generating layer and that of the p-type charge generating layer may be each independently in a range of about 20 .ANG. to about 1,000 .ANG.. According to an embodiment, the thickness of the n-type charge generating layer and that of the p-type charge generating layer may be each independently in a range of about 50 .ANG. to about 500 .ANG.. According to an embodiment, the thickness of the n-type charge generating layer may be in a range of about 100 .ANG. to about 300 .ANG., and the thickness of the p-type charge generating layer may be in a range of about 50 .ANG. to about 200 .ANG., but embodiments are not limited thereto.

According to an embodiment, the organic light-emitting device 10 may further include a hole transport region between the first electrode and an emission unit adjacent to the first electrode from among the m emission units, wherein the hole transport region may include a p-dopant having a LUMO energy level of about -3.5 eV or less. The p-dopant may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments are not limited thereto. In some embodiments, the p-dopant may include at least one selected from the group consisting of:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and/or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide and/or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

compounds represented by Formula 221, but is not limited thereto.

FIG. 2 illustrates a schematic view of an organic light-emitting device 11 according to an embodiment. According to an embodiment, as shown in FIG. 2, the organic light-emitting device 11 may further include an electron transport layer 157 between the emission unit 153 adjacent to the second electrode 190 from among the m emission units 153 and the second electrode 190.

The electron transport layer 157 may include a metal-containing material and an electron transporting metal-non-containing material (e.g., an electron transporting material that does not include metal).

The metal-containing material may include a metal, a metal complex, or a combination thereof.

In some embodiments, when the electron transport layer includes a metal as the metal-containing material, the metal may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof. In some embodiments, when the electron transport layer includes a metal as the metal-containing material, the metal may be selected from lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), francium (Fr), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), radium (Ra), La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. According to an embodiment, when the electron transport layer includes a metal as the metal-containing material, the metal may be selected from Li, Mg, and Yb, but embodiments are not limited thereto.

In some embodiments, when the electron transport layer includes a metal complex as the metal-containing material, the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof. In some embodiments, when the electron transport layer includes a metal complex as the metal-containing material, the metal complex may include Li, Al, Ti, Zr, Hf, Zn, and/or Cu. According to an embodiment, when the electron transport layer includes a metal complex as the metal-containing material, the metal complex may be a Li complex or an Al complex, but embodiments are not limited thereto.

When the electron transport layer includes a metal complex as the metal-containing material, the metal complex may further include at least one organic ligand selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene. In some embodiments, when the electron transport layer includes a metal complex as the metal-containing material, the metal complex may include at least one selected from a substituted or unsubstituted hydroxyquinoline and a substituted or unsubstituted hydroxyphenylbenzothiazole.

In some embodiments, when the electron transport layer includes a metal complex as the metal-containing material, the metal complex may be a lithium quinolate (Liq) and/or an aluminum quinolate (Alq.sub.3).

The electron transporting metal-non-containing material included in the electron transport layer may be an organic compound including at least one .pi. electron-depleted nitrogen-containing ring. In some embodiments, the electron transporting metal-non-containing material may be an organic compound including at least one selected from an imidazole ring, a pyrazole ring, a thiazole ring, an isothiazole ring, an oxazole ring, an isoxazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, an indazole ring, a purine ring, a quinoline ring, an isoquinoline ring, a benzoquinoline ring, a phthalazine ring, a naphthyridine ring, a quinoxaline ring, a quinazoline ring, a cinnoline ring, a phenanthridine ring, an acridine ring, a phenanthroline ring, a phenazine ring, a benzoimidazole ring, an iso-benzothiazole ring, a benzoxazole ring, an isobenzoxazole ring, a triazole ring, a tetrazole ring, an oxadiazole ring, a triazine ring, a thiadiazole ring, an imidazopyridine ring, an imidazopyrimidine ring, and indenoquinoline ring. In some embodiments, the electron transporting metal-non-containing material may be an organic compound including at least one selected from a phenanthroline ring, an imidazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring. In some embodiments, the electron transporting metal-non-containing material may be selected from Compounds 1 to 6 (as illustrated above).

In some embodiments, the metal-containing material and the electron transporting metal-non-containing material included in at least one of the m-1 n-type charge generating layer(s) may be the same as the metal-containing material and the electron transporting metal-non-containing material included in the electron transport layer, respectively. In some embodiments, at least one of the m-1 n-type charge generating layer(s) may include Yb as the metal-containing material and Compound 1 as the electron transporting metal-non-containing material. The electron transport layer may include Yb as the metal-containing material and Compound 1 as the electron transporting metal-non-containing material.

According to some embodiments, the metal-containing material included in at least one of the m-1 n-type charge generating layer(s) may differ from the metal-containing material included in the electron transport layer; the electron transporting metal-non-containing material included in at least one of the m-1 n-type charge generating layer(s) may differ from the electron transporting metal-non-containing material included in the electron transport layer; or the metal-containing material included in at least one of the m-1 n-type charge generating layer(s) may differ from the metal-containing material included in the electron transport layer, and the electron transporting metal-non-containing material included in at least one of the m-1 n-type charge generating layer(s) may differ from the electron transporting metal-non-containing material included in the electron transport layer.

In some embodiments, at least one of the m-1 n-type charge generating layer(s) may include Yb as the metal-containing material and Compound 1 as the electron transporting metal-non-containing material. The electron transport layer may include Li as the metal-containing material and Compound 1 as the electron transporting metal-non-containing material. In some embodiments, at least one of the m-1 n-type charge generating layer(s) may include Yb as the metal-containing material and Compound 1 as the electron transporting metal-non-containing material. The electron transport layer may include Liq as the metal-containing material and Compound 5 as the electron transporting metal-non-containing material.

According to some embodiments, m may be 3 or greater, and the m-1 n-type charge generating layers may all include the same metal-containing material and the same electron transporting metal-non-containing material, and

the metal-containing material included in the m-1 n-type charge generating layers may differ from the metal-containing material included in the electron transport layer; the electron transporting metal-non-containing material included in the m-1 n-type charge generating layers may differ from the electron transporting metal-non-containing material included in the electron transport layer; or the metal-containing material included in the m-1 n-type charge generating layers may differ from the metal-containing material included in the electron transport layer, and the electron transporting metal-non-containing material included in the m-1 n-type charge generating layers may differ from the electron transporting metal-non-containing material included in the electron transport layer.

According to an embodiment, the organic light-emitting device 11 may further include, in addition to an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units, a hole transport region between the first electrode and an emission unit adjacent to the first electrode from among the m emission units, wherein the hole transport region may include a p-dopant having a LUMO energy level of about -3.5 eV or less. The p-dopant may be the same as described herein.

In an organic light-emitting device according to an embodiment, m may be 2. That is, in some embodiments, the organic light-emitting device may include only two emission units. In some embodiments, an organic light-emitting device may include a first electrode, a first emission unit, a first charge generating layer, a second emission unit, and a second electrode, which are stacked in this stated order. The organic light-emitting device may further include an electron transport layer between the second emission unit and the second electrode.

In an organic light-emitting device according to another embodiment, m may be 3. That is, in some embodiments, the organic light-emitting device may include only three emission units. In some embodiments, an organic light-emitting device may include a first electrode, a first emission unit, a first charge generating layer, a second emission unit, a second charge generating layer, a third emission unit, and a second electrode, which are stacked in this stated order. The organic light-emitting device may further include an electron transport layer between the third emission unit and the second electrode.

According to another embodiment, an organic light-emitting device may include a first electrode;

a second electrode facing the first electrode;

m emission units stacked between the first electrode and the second electrode; and

m-1 charge generating layer(s) between the two adjacent emission units from among the m emission units, m-1 charge generating layer(s) including m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s),

wherein m may be an integer of 2 or greater,

a maximum emission wavelength of light emitted from at least one of the m emission units may differ from that of light emitted from at least one of the other emission units,

at least one of the m-1 n-type charge generating layer(s) may include a metal-containing material and an electron transporting metal-non-containing material,

the metal-containing material may include a metal, a metal complex, or a combination thereof,

the metal may include a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and

the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof.

The organic light-emitting device may further include an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units,

wherein the electron transport layer may include a metal-containing material and an electron transporting metal-non-containing material,

the metal-containing material may include a metal, a metal complex, or a combination thereof,

the metal may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and

the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof.

According to another embodiment, an organic light-emitting device may include a first electrode;

a second electrode facing the first electrode;

m emission units stacked between the first electrode and the second electrode; and

m-1 charge generating layer(s) between two adjacent emission units from among the m emission units and including m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s),

wherein m may be an integer of 2 or greater,

a maximum emission wavelength of light emitted from at least one of the m emission units may differ from that of light emitted from at least one of the other emission units,

at least one of the m-1 n-type charge generating layer(s) may include a metal-containing material and an electron transporting metal-non-containing material,

the metal-containing material may include a metal, a metal complex, or a combination thereof,

the metal may include a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and

the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof.

The organic light-emitting device may further include an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units,

wherein the electron transport layer may include a metal-containing material and an electron transporting metal-non-containing material,

the metal-containing material may include a metal, a metal complex, or a combination thereof,

the metal may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and

the metal complex may include an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof.

When the n-type charge generating layer includes a metal-containing material and an electron transporting metal-non-containing material, wherein the metal-containing material is a metal including a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the metal may have relatively great atomic weight or size compared to an alkali metal, and thus may exhibit no or reduced intermixing with peripheral layers. Accordingly, an organic light-emitting device including the n-type charge generating layer according to embodiments of the present disclosure may have long lifespan and/or improved stability.

In addition, when the n-type charge generating layer includes a metal-containing material and an electron transporting metal-non-containing material, wherein the metal-containing material is a metal complex, the metal in the metal complex may be stabilized by a ligand (e.g., an organic ligand included in the metal complex). Accordingly, an organic light-emitting device including the n-type charge generating layer according to embodiments of the present disclosure may have improved stability due to interaction between the metal complex and the electron transporting metal-non-containing material.

In addition, when the n-type charge generating layer includes a metal-containing material and an electron transporting metal-non-containing material, wherein the metal-containing material includes both a metal of a rare-earth metal, a transition metal, a late transition metal, or a combination thereof and a metal complex, an organic light-emitting device including the n-type charge generating layer may have both of the foregoing advantages.

Description of FIG. 3

FIG. 3 is a schematic cross-sectional view illustrating an organic light-emitting device 12 according to an embodiment. The organic light-emitting device 12 may include the first electrode 110, the organic layer 150, and the second electrode 190.

Hereinafter, the structure of the organic light-emitting device 12 according to an embodiment and a method of manufacturing an organic light-emitting device according to an embodiment will be described in connection with FIG. 3.

First Electrode 110

In FIG. 3, a substrate may be additionally disposed under the first electrode 110 or above the second electrode 190. The substrate may be a glass substrate or a plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and/or water-resistance.

The first electrode 110 may be formed by depositing or sputtering a material for the first electrode 110 on the substrate. When the first electrode 110 is an anode, a material for the first electrode 110 may be selected from materials with a high work function to facilitate hole injection.

The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for the first electrode 110 may be selected from indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), zinc oxide (ZnO), and any combinations thereof, but is not limited thereto. In one or more embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for the first electrode 110 may be selected from magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al--Li), calcium (Ca), magnesium-indium (Mg--In), magnesium-silver (Mg--Ag), and any combinations thereof, but is not limited thereto.

The first electrode 110 may have a single-layered structure, or a multi-layered structure including two or more layers. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 110 is not limited thereto.

Organic Layer 150

The organic layer 150 may be positioned on the first electrode 110. The organic layer 150 may include an emission unit.

The organic layer 150 may further include a hole transport region between the first electrode 110 and the emission unit and an electron transport region between the emission unit and the second electrode 190.

Hole Transport Region in Organic Layer 150

The hole transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from a hole injection layer, a hole transport layer, an emission auxiliary layer, and an electron blocking layer.

For example, the hole transport region may have a single-layered structure including a single layer including a plurality of different materials, or a multi-layered structure of hole injection layer/hole transport layer, hole injection layer/hole transport layer/emission auxiliary layer, hole injection layer/emission auxiliary layer, hole transport layer/emission auxiliary layer, or hole injection layer/hole transport layer/electron blocking layer, wherein for each structure, constituting layers are sequentially stacked from the first electrode 110 in this stated order, but the structure of the hole transport region is not limited thereto.

The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB (NPD), .beta.-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated NPB, TAPC, HMTPD, 4,4',4''-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (Pani/CSA), polyaniline/poly(4-styrenesulfonate) (Pani/PSS), a compound represented by Formula 201, and a compound represented by Formula 202:

##STR00007## ##STR00008## ##STR00009##

wherein, in Formulae 201 and 202,

L.sub.201 to L.sub.204 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 arylene group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

L.sub.205 may be selected from *--O--*', *--S--', *--N(Q.sub.201)-*', a substituted or unsubstituted C.sub.1-C.sub.20 alkylene group, a substituted or unsubstituted C.sub.2-C.sub.20 alkenylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 arylene group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xa1 to xa4 may be each independently an integer selected from 0 to 3,

xa5 may be an integer selected from 1 to 10, and

R.sub.201 to R.sub.204 and Q.sub.201 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.

In some embodiments, in Formula 202, R.sub.201 and R.sub.202 may optionally be bound to each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R.sub.203 and R.sub.204 may optionally be bound to each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In some embodiments, in Formulae 201 and 202,

L.sub.201 to L.sub.205 may be each independently selected from the group consisting of:

a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, and a pyridinylene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with --F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), and --N(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may each be independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may be each independently 0, 1, or 2.

According to an embodiment, xa5 may be 1, 2, 3, or 4.

According to some embodiments, R.sub.201 to R.sub.204 and Q.sub.201 may be each independently selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with --F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), and --N(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may be the same as described herein.

According to some embodiments, at least one selected from R.sub.201 to R.sub.203 in Formula 201 may be selected from the group consisting of:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with --F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group,

but embodiments are not limited thereto.

According to some embodiments, in Formula 202, i) R.sub.201 and R.sub.202 may be bound to each other via a single bond, and/or ii) R.sub.203 and R.sub.204 may be bound to each other via a single bond.

According to some embodiments, at least one selected from R.sub.201 to R.sub.204 in Formula 202 may be selected from the group consisting of:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with --F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, but embodiments are not limited thereto.

The compound represented by Formula 201 may be represented by Formula 201A:

##STR00010##

In some embodiments, the compound represented by Formula 201 may be represented by Formula 201A(1), but embodiments are not limited thereto:

##STR00011##

In some embodiments, the compound represented by Formula 201 may be represented by Formula 201A-1, but embodiments are not limited thereto:

##STR00012##

In some embodiments, the compound represented by Formula 202 may be represented by Formula 202A, but embodiments are not limited thereto:

##STR00013##

In some embodiments, the compound represented by Formula 202 may be represented by Formula 202A-1:

##STR00014##

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

descriptions of L.sub.201 to L.sub.203, xa1 to xa3, xa5, and R.sub.202 to R.sub.204 may each independently be the same as descriptions thereof provided herein,

descriptions of R.sub.211 and R.sub.212 may each independently be the same as the description provided herein in connection with R.sub.203, and

R.sub.213 to R.sub.217 may be each independently selected from hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with --F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group.

For example, the hole transport region may include at least one compound selected from Compounds HT1 to HT39, but embodiments are not limited thereto:

##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021##

The thickness of the hole transport region may be in a range of about 100 .ANG. to about 10,000 .ANG., for example, about 100 .ANG. to about 1,000 .ANG.. When the hole transport region includes at least one selected from a hole injection layer and a hole transport layer, the thickness of the hole injection layer may be in a range of about 100 .ANG. to about 9,000 .ANG., and in some embodiments, about 100 .ANG. to about 1,000 .ANG.; the thickness of the hole transport layer may be in a range of about 50 .ANG. to about 2,000 .ANG., and in some embodiments, about 100 .ANG. to about 1,500 .ANG.. When the thicknesses of the hole transport region, the hole injection layer and the hole transport layer are within any of these ranges, satisfactory (or suitable) hole transporting characteristics may be obtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase the light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer, and the electron blocking layer may block or reduce the flow of electrons from an electron transport region. The emission auxiliary layer and the electron blocking layer may each independently include any of the materials as described above.

p-Dopant

The hole transport region may further include, in addition to the materials described above, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The charge-generation material may be, for example, a p-dopant.

In one embodiment, the p-dopant may have a lowest unoccupied molecular orbital (LUMO) of -3.5 eV or less.

The p-dopant may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments are not limited thereto.

In some embodiments, the p-dopant may include at least one selected from the group consisting of:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and/or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide and/or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

compounds represented by Formula 221, but embodiments are not limited thereto:

##STR00022##

wherein, in Formula 221,

R.sub.221 to R.sub.223 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, provided that at least one selected from R.sub.221 to R.sub.223 may include at least one substituent selected from a cyano group, --F, --Cl, --Br, --I, a C.sub.1-C.sub.20 alkyl group substituted with --F, a C.sub.1-C.sub.20 alkyl group substituted with --Cl, a C.sub.1-C.sub.20 alkyl group substituted with --Br, and a C.sub.1-C.sub.20 alkyl group substituted with --I.

Emission Layer in Organic Layer 150

In the organic light-emitting device 12, an emission unit may include an emission layer, wherein the emission layer may have a stacked structure of two or more layers selected from a red emission layer, a green emission layer, a yellow emission layer, and a blue emission layer, in which the two or more layers may contact each other or may be separated from each other. In one or more embodiments, the emission layer may include two or more materials selected from a red-light emission material, a green-light emission material, a yellow-light emission material, and a blue-light emission material, in which the two or more materials may be mixed together in a single layer.

The emission unit may further include an upper auxiliary layer formed on the emission layer and/or a lower auxiliary layer formed below (e.g., under) the emission layer. The lower auxiliary layer may perform substantially the same functions as the above-described hole transport layer, emission auxiliary layer, and electron blocking layer; and the upper auxiliary layer may perform substantially the same functions as the below-described buffer layer, hole blocking layer, electron control layer, and electron transport layer. The materials for the lower auxiliary layer and the upper auxiliary layer may be the same as those described herein in connection with the materials for the hole transport region and the electron transport region.

The emission layer may include a host and a dopant. The dopant may include at least one selected from a phosphorescent dopant and a fluorescent dopant.

The amount of the dopant in the emission layer may be in a range of about 0.01 to about 15 parts by weight based on 100 parts by weight of the host, but is not limited thereto.

The thickness of the emission layer may be in a range of about 100 .ANG. to about 1,000 .ANG., in some embodiments, about 200 .ANG. to about 600 .ANG.. When the thickness of the emission layer is within any of these ranges, excellent (or suitable) light-emission characteristics may be obtained without a substantial increase in driving voltage.

Host in Emission Layer

The host may include a compound represented by Formula 301: [Ar.sub.301].sub.xb11-[(L.sub.301).sub.xb1-R.sub.301].sub.xb21, Formula 301

wherein, in Formula 301,

Ar.sub.301 may be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

xb11 may be 1, 2, or 3,

L.sub.301 may be selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xb1 may be an integer selected from 0 to 5,

R.sub.301 may be selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.301)(Q.sub.302)(Q.sub.303), --N(Q.sub.301)(Q.sub.302), --B(Q.sub.301)(Q.sub.302), --C(.dbd.O)(Q.sub.301), --S(.dbd.O).sub.2(Q.sub.301), and --P(.dbd.O)(Q.sub.301)(Q.sub.302), and

xb21 may be an integer selected from 1 to 5,

wherein Q.sub.301 to Q.sub.303 may be each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments are not limited thereto.

In some embodiments, Ar.sub.301 in Formula 301 may be selected from the group consisting of:

a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, and a dibenzothiophene group; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, and a dibenzothiophene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --N(Q.sub.31)(Q.sub.32), --B(Q.sub.31)(Q.sub.32), --C(.dbd.O)(Q.sub.31), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may be each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments are not limited thereto.

When xb11 in Formula 301 is 2 or greater, a plurality of Ar.sub.301(s) may be bound to a respective one another via a single bond.

In one or more embodiments, the compound represented by Formula 301 may be represented by Formula 301-1 or 301-2:

##STR00023##

wherein, in Formulae 301-1 to 301-2,

A.sub.301 to A.sub.304 may be each independently selected from a benzene group, a naphthalene group, a phenanthrene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a pyridine group, a pyrimidine group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, an indole group, a carbazole group, a benzocarbazole group, a dibenzocarbazole group, a furan group, a benzofuran group, a dibenzofuran group, a naphthofuran group, a benzonaphthofuran group, a dinaphthofuran group, a thiophene group, a benzothiophene group, a dibenzothiophene group, a naphthothiophene group, a benzonaphthothiophene group, and a dinaphthothiophene group,

X.sub.301 may be O, S, or N-[(L.sub.304).sub.xb4-R.sub.304],

R.sub.311 to R.sub.314 may be each independently selected from hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --N(Q.sub.31)(Q.sub.32), --B(Q.sub.31)(Q.sub.32), --C(.dbd.O)(Q.sub.31), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

xb22 and xb23 may be each independently 0, 1, or 2,

descriptions of L.sub.301, xb1, R.sub.301, and Q.sub.31 to Q.sub.33 may each independently be the same as those provided herein,

descriptions of L.sub.302 to L.sub.304 may be each independently the same as the description provided herein in connection with L.sub.301,

descriptions of xb2 to xb4 may be each independently the same as the description provided herein in connection with xb1, and

descriptions of R.sub.302 to R.sub.304 may be each independently the same as the description provided herein in connection with R.sub.301.

In some embodiments, L.sub.301 to L.sub.304 in Formulae 301, 301-1, and 301-2 may be each independently selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --N(Q.sub.31)(Q.sub.32), --B(Q.sub.31)(Q.sub.32), --C(.dbd.O)(Q.sub.31), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may be the same as those described herein.

In some embodiments, R.sub.301 to R.sub.304 in Formulae 301, 301-1, and 301-2 may be each independently selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --N(Q.sub.31)(Q.sub.32), --B(Q.sub.31)(Q.sub.32), --C(.dbd.O)(Q.sub.31), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may be the same as those described herein.

In one or more embodiments, the host may include an alkaline earth metal complex. For example, the host may be selected from a beryllium (Be) complex (e.g., Compound H55 illustrated below), a magnesium (Mg) complex, and a zinc (Zn) complex.

The host may include at least one selected from 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55, but embodiments are not limited thereto:

##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## ##STR00035## Phosphorescent Dopant Included in an Emission Layer of the Organic Layer 150

The phosphorescent dopant may include an organometallic complex represented by Formula 401:

##STR00036##

wherein, in Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd), osmium

(Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), and thulium (Tm),

L.sub.401 may be selected from ligands represented by Formula 402, and xc1 may be 1, 2, or 3; when xc1 is 2 or greater, a plurality of L.sub.401(s) may be identical to or different from each other,

L.sub.402 may be an organic ligand, and xc2 may be an integer selected from 0 to 4; when xc2 is 2 or greater, a plurality of L.sub.402(s) may be identical to or different from each other,

X.sub.401 to X.sub.404 may be each independently nitrogen (N) or carbon (C),

X.sub.401 and X.sub.403 are bound to each other via a single bond or a double bond;

X.sub.402 and X.sub.404 are bound to each other via a single bond or a double bond,

A.sub.401 and A.sub.402 may be each independently a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group,

X.sub.405 may be a single bond, *--O--*', *--C(.dbd.O)--*', *--N(Q.sub.411)-*', *--C(Q.sub.411)(Q.sub.412)-*', *--C(Q.sub.411)=C(Q.sub.412)-*', *--C(Q.sub.411)=*', or *.dbd.C(Q.sub.411)=*', wherein Q.sub.411 and Q.sub.412 may be each independently selected from hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group,

X.sub.406 may be a single bond, O, or S,

R.sub.401 and R.sub.402 may be each independently selected from hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.20 alkyl group, a substituted or unsubstituted C.sub.1-C.sub.20 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.401)(Q.sub.402)(Q.sub.403), --N(Q.sub.401)(Q.sub.402), --B(Q.sub.401)(Q.sub.402), --C(.dbd.O)(Q.sub.401), --S(.dbd.O).sub.2(Q.sub.401), and --P(.dbd.O)(Q.sub.401)(Q.sub.402), wherein Q.sub.401 to Q.sub.403 may be each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a C.sub.6-C.sub.20 aryl group, and a C.sub.1-C.sub.20 heteroaryl group,

xc11 and xc12 may be each independently an integer selected from 0 to 10, and

* and *' in Formula 402 may each independently indicate a binding site to M in Formula 401.

According to an embodiment, A.sub.401 and A.sub.402 in Formula 402 may be each independently selected from a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, an indene group, a pyrrole group, a thiophene group, a furan group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a quinoxaline group, a quinazoline group, a carbazole group, a benzoimidazole group, a benzofuran group, a benzothiophene group, an isobenzothiophene group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a dibenzofuran group, and a dibenzothiophene group.

In one or more embodiments, in Formula 402, i) X.sub.401 may be nitrogen, and X.sub.402 may be carbon, or ii) X.sub.401 and X.sub.402 may both be nitrogen.

According to some embodiments, R.sub.401 and R.sub.402 in Formula 402 may be each independently selected from the group consisting of:

hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, and a C.sub.1-C.sub.20 alkoxy group;

a C.sub.1-C.sub.20 alkyl group and a C.sub.1-C.sub.20 alkoxy group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornanyl group, and a norbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornanyl group, a norbornenyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornanyl group, a norbornenyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornanyl group, a norbornenyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group; and

--Si(Q.sub.401)(Q.sub.402)(Q.sub.403), --N(Q.sub.401)(Q.sub.402), --B(Q.sub.401)(Q.sub.402), --C_(.dbd.O) (Q.sub.401), --S(.dbd.O).sub.2(Q.sub.401), and --P(.dbd.O)(Q.sub.401)(Q.sub.402),

wherein Q.sub.401 to Q.sub.403 may be each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, and a naphthyl group, but embodiments are not limited thereto.

In one or more embodiments, when xc1 in Formula 401 is 2 or greater, two A.sub.401(s) in a plurality of L.sub.401(s) may optionally be bound to each other via X.sub.407 as a linking group, and two A.sub.402(s) may optionally be bound to each other via X.sub.408 as a linking group (see e.g., Compounds PD1 to PD4 and PD7). X.sub.407 and X.sub.408 may be each independently selected from a single bond, *--O--*', *--C(.dbd.O)--*', *--N(Q.sub.413)-*', *--C(Q.sub.413)(Q.sub.414)-*' or *--C(Q.sub.413)=C(Q.sub.414)-*' wherein, Q.sub.413 and Q.sub.414 may be each independently selected from hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group, but embodiments are not limited thereto.

L.sub.402 in Formula 401 may be any suitable monovalent, divalent, or trivalent organic ligand. In some embodiments, L.sub.402 may be selected from halogen, diketone (e.g., acetylacetonate), a carboxylic acid (e.g., picolinate), --C(.dbd.O), isonitrile, --CN, and phosphorus (e.g., phosphine and/or phosphite), but embodiments are not limited thereto.

In some embodiments, the phosphorescent dopant may include, for example, at least one selected from Compounds PD1 to PD25, but embodiments are not limited thereto:

##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## Fluorescent Dopant in Emission Layer

The fluorescent dopant may include an arylamine compound or a styrylamine compound.

In some embodiments, the fluorescent dopant may include a compound represented by Formula 501:

##STR00042##

wherein, in Formula 501,

Ar.sub.501 may be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

L.sub.501 to L.sub.503 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 arylene group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xd1 to xd3 may be each independently an integer selected from 0 to 3,

R.sub.501 and R.sub.502 may be each independently selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, and

xd4 may be an integer selected from 1 to 6.

In some embodiments, Ar.sub.5o1 in Formula 501 may be selected from the group consisting of:

a naphthalene group, a heptalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, and an indenophenanthrene group; and

a naphthalene group, a heptalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, and an indenophenanthrene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In one or more embodiments, L.sub.501 to L.sub.503 in Formula 501 may be each independently selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, and a pyridinylene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group.

According to some embodiments, R.sub.501 and R.sub.501 in Formula 502 may be each independently selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, and --Si(Q.sub.31)(Q.sub.32)(Q.sub.33),

wherein Q.sub.31 to Q.sub.33 may each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2, but embodiments are not limited thereto.

In some embodiments, the fluorescent dopant may be selected from Compounds FD1 to FD22:

##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048##

In some embodiments, the fluorescent dopant may be selected from the compounds below, but embodiments are not limited thereto:

##STR00049## Electron Transport Region in Organic Layer 150

The electron transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, and an electron injection layer, but is not limited thereto.

In some embodiments, the electron transport region may have a structure of electron transport layer/electron injection layer, a structure of hole blocking layer/electron transport layer/electron injection layer, a structure of electron control layer/electron transport layer/electron injection layer, or a structure of buffer layer/electron transport layer/electron injection layer, wherein the layers of these structures are sequentially stacked in these stated orders on an emission layer. However, the structure of the electron transport region is not limited thereto.

The electron transport region (e.g., a buffer layer, a hole blocking layer, an electron control layer, and/or an electron transport layer in the electron transport region) may include a metal-free compound containing at least one .pi. electron-depleted nitrogen-containing ring.

The term ".pi. electron-depleted nitrogen-containing ring" as used herein may refer to a C.sub.1-C.sub.60 heterocyclic group having at least one *--N.dbd.*' moiety as a ring-forming moiety.

For example, the ".pi. electron-depleted nitrogen-containing ring" may be i) a 5-membered to 7-membered heteromonocyclic group having at least one *--N.dbd.*' moiety, ii) a heteropolycyclic group in which two or more 5-membered to 7-membered heteromonocyclic groups each having at least one *--N.dbd.*' moiety are condensed (e.g., fused), or iii) a heteropolycyclic group in which at least one 5-membered to 7-membered heteromonocyclic group having at least one *--N.dbd.*' moiety, is condensed (e.g., fused) with at least one C.sub.5-C.sub.60 carbocyclic group.

Non-limiting examples of the .pi. electron-depleted nitrogen-containing ring may include an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, an indazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, a phthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline, a phenanthridine, an acridine, a phenanthroline, a phenazine, a benzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole, a triazine, thiadiazole, an imidazopyridine, an imidazopyrimidine, and an azacarbazole, but are not limited thereto.

In some embodiments, the electron transport region may include a compound represented by Formula 601: [Ar.sub.601].sub.xe11-[(L.sub.601).sub.xe1-R.sub.601].sub.xe21, Formula 601

wherein, in Formula 601,

Ar.sub.601 may be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

xe11 may be 1, 2, or 3,

L.sub.601 may be selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkylene group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenylene group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenylene group, a substituted or unsubstituted C.sub.6-C.sub.60 arylene group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group,

xe1 may be an integer selected from 0 to 5,

R.sub.601 may be selected from a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.601)(Q.sub.602)(Q.sub.603), --C(.dbd.O)(Q.sub.601), --S(.dbd.O).sub.2(Q.sub.601), and --P(.dbd.O)(Q.sub.601)(Q.sub.602),

wherein Q.sub.601 to Q.sub.603 may be each independently a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, and

xe21 may be an integer selected from 1 to 5.

In some embodiments, at least one selected from the xe11 number of Ar.sub.601(s) and the xe21 number of R.sub.601(s) may include a .pi. electron-depleted nitrogen-containing ring.

In some embodiments, ring Ar.sub.601 in Formula 601 may be selected from the group consisting of:

a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzoimidazole group, an iso-benzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, and indenoquinoline group; and

a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzoimidazole group, an iso-benzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, and indenoquinoline group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, --Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

wherein Q.sub.31 to Q.sub.33 may be each independently selected from a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

When xe11 in Formula 601 is 2 or greater, a plurality of Ar.sub.601(s) may be bound to each other via a single bond.

In one embodiment, Ar.sub.601 in Formula 601 may be an anthracene group.

In some embodiments, the compound represented by Formula 601 may be represented by Formula 601-1:

##STR00050##

wherein, in Formula 601-1,

X.sub.614 may be N or C(R.sub.614), X.sub.615 may be N or C(R.sub.615), X.sub.616 may be N or C(R.sub.616), and at least one selected from X.sub.614 to X.sub.616 may be N,

descriptions of L.sub.611 to L.sub.613 may be each independently the same as the description provided herein in connection with L.sub.601,

descriptions of xe611 to xe613 may be each independently the same as the description provided herein in connection with xe1,

descriptions of R.sub.611 to R.sub.613 may be each independently substantially the same as the description provided herein in connection with R.sub.601, and

R.sub.614 to R.sub.616 may be each independently selected from hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.

In one embodiment, L.sub.601 and L.sub.611 to L.sub.613 in Formulae 601 and 601-1 may be each independently selected from the group consisting of:

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, a spiro-bifluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a thiophenylene group, a furanylene group, a carbazolylene group, an indolylene group, an isoindolylene group, a benzofuranylene group, a benzothiophenylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, a dibenzosilolylene group, a pyridinylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a thiadiazolylene group, an oxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a triazinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzoimidazolylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an imidazopyridinylene group, an imidazopyrimidinylene group, and an azacarbazolylene group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, but embodiments are not limited thereto.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may be each independently selected from 0, 1, and 2.

In some embodiments, R.sub.601 and R.sub.611 to R.sub.613 in Formulae 601 and 601-1 may be each independently selected from the group consisting of:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, and an azacarbazolyl group; and

--S(.dbd.O).sub.2(Q.sub.601) and --P(.dbd.O)(Q.sub.601)(Q.sub.602),

wherein Q.sub.601 and Q.sub.602 may be each independently the same as described herein.

The electron transport region may include at least one compound selected from Compounds ET1 to ET36, but embodiments are not limited thereto:

##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061##

In one or more embodiments, the electron transport region may include at least one compound selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq.sub.3, BAlq, 3-(Biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), and NTAZ:

##STR00062##

The thickness of the buffer layer, the hole blocking layer, and the electron control layer may be each independently in a range of about 20 .ANG. to about 1,000 .ANG.. When the thicknesses of the buffer layer, the hole blocking layer, and the electron control layer are each within any of these ranges, the electron transport region may have excellent (or suitable) hole blocking characteristics or electron control characteristics without a substantial increase in driving voltage.

The thickness of the electron transport layer may be in a range of about 100 .ANG. to about 1,000 .ANG., and in some embodiments, about 150 .ANG. to about 500 .ANG.. When the thickness of the electron transport layer is within any of these ranges, the electron transport layer may have satisfactory (or suitable) electron transport characteristics without a substantial increase in driving voltage.

The electron transport region (e.g., the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

The metal-containing material may include at least one selected from an alkali metal complex and an alkaline earth metal complex. The alkali metal complex may include a metal ion selected from an Li ion, a Na ion, a K ion, a Rb ion, and a Cs ion, and the alkaline earth metal complex may include a metal ion selected from a Be ion, a Mg ion, a Ca ion, an Sr ion, and a Ba ion. Ligands respectively coordinated with the metal ion of the alkali metal complex or the alkaline earth metal complex may be each independently selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, but embodiments are not limited thereto.

In some embodiments, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) and/or Compound ET-D2:

##STR00063##

The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 190. The electron injection layer may directly contact the second electrode 190.

The electron injection layer may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare-earth metal, an alkali metal compound, an alkaline earth metal compound, a rare-earth metal compound, an alkali metal complex, an alkaline earth metal complex, a rare-earth metal complex, or a combination thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In one embodiment, the alkali metal may be selected from Li, Na, and Cs. In one or more embodiments, the alkali metal may be Li or Cs, but is not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare-earth metal may be selected from Sc, Y, Ce, Tb, Yb, Gd, and Tb.

The alkali metal compound, the alkaline earth metal compound, and the rare-earth metal compound may be each independently selected from oxides and halides (e.g., fluorides, chlorides, bromides, and/or iodines) of the alkali metal, the alkaline earth metal, and the rare-earth metal, respectively.

In some embodiments, the alkali metal compound may be selected from alkali metal oxides (such as Li.sub.2O, Cs.sub.2O, and/or K.sub.2O) and alkali metal halides (such as LiF, NaF, CsF, KF, LiI, NaI, CsI, and/or KI). In one embodiment, the alkali metal compound may be selected from LiF, Li.sub.2O, NaF, LiI, NaI, CsI, and KI, but is not limited thereto.

The alkaline earth metal compound may be selected from alkaline earth metal compounds, such as BaO, SrO, CaO, Ba.sub.xSr.sub.1-xO (wherein 0<x<1), and/or Ba.sub.xCa.sub.1-xO (wherein 0<x<1). In one embodiment, the alkaline earth metal compound may be selected from BaO, SrO, and CaO, but is not limited thereto.

The rare-earth metal compound may be selected from YbF.sub.3, ScF.sub.3, ScO.sub.3, Y.sub.2O.sub.3, Ce.sub.2O.sub.3, GdF.sub.3, and TbF.sub.3. In one embodiment, the rare-earth metal compound may be selected from YbF.sub.3, ScF.sub.3, TbF.sub.3, YbI.sub.3, ScI.sub.3, and TbI.sub.3, but is not limited thereto.

The alkali metal complex, the alkaline earth metal complex, and the rare-earth metal complex may include an alkali metal ion, and alkaline earth metal ion, and a rare-earth metal ion, respectively, as described above, and ligands respectively coordinated with the metal ion of the alkali metal complex, the alkaline earth metal complex, and the rare-earth metal complex may each independently be selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, but are not limited thereto.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare-earth metal, an alkali metal compound, an alkaline earth metal compound, a rare-earth metal compound, an alkali metal complex, an alkaline earth metal complex, an rare-earth metal complex, or a combination thereof, as described above. In one or more embodiments, the electron injection layer may further include an organic material. When the electron injection layer further includes an organic material, an alkali metal, an alkaline earth metal, a rare-earth metal, an alkali metal compound, an alkaline earth metal compound, a rare-earth metal compound, an alkali metal complex, an alkaline earth metal complex, a rare-earth metal complex, or a combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

A thickness of the electron injection layer may be in a range of about 1 .ANG. to about 100 .ANG., and in some embodiments, about 3 .ANG. to about 90 .ANG.. When the thickness of the electron injection layer is within any of these ranges, the electron injection layer may have satisfactory (or suitable) electron injection characteristics without a substantial increase in driving voltage.

Second Electrode 190

The second electrode 190 may be disposed on the organic layer 150. The second electrode 190 may be a cathode, which is an electron injection electrode, and in this regard, a material for forming the second electrode 190 may be selected from a metal, an alloy, an electrically conductive compound, and a combination thereof, each having a relatively low work function.

The second electrode 190 may include at least one selected from lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al--Li), calcium (Ca), magnesium-indium (Mg--In), magnesium-silver (Mg--Ag), ITO, and IZO, but is not limited thereto. The second electrode 190 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or a multi-layered structure including two or more layers.

Description of FIGS. 4 to 6

An organic light-emitting device 20 represented by FIG. 4 includes a first capping layer 210, the first electrode 110, the organic layer 150, and the second electrode 190 sequentially stacked in this stated order. An organic light-emitting device 30 represented by FIG. 5 includes the first electrode 110, the organic layer 150, the second electrode 190, and a second capping layer 220 sequentially stacked in this stated order. An organic light-emitting device 40 represented by FIG. 6 includes the first capping layer 210, the first electrode 110, the organic layer 150, the second electrode 190, and the second capping layer 220 sequentially stacked in this stated order.

Regarding FIGS. 4 to 6, descriptions of the first electrode 110, the organic layer 150, and the second electrode 190 may be each independently the same as those provided herein in connection with FIG. 1.

In the organic light-emitting devices 20 and 40, light emitted from the emission layer in the organic layer 150 may pass through the first electrode 110 (which may be a semi-transmissive electrode or a transmissive electrode) and through the first capping layer 210 to the outside. In the organic light-emitting devices 30 and 40, light emitted from the emission layer in the organic layer 150 may pass through second electrode 190 (which may be a semi-transmissive electrode or a transmissive electrode) and through the second capping layer 220 to the outside.

The first capping layer 210 and the second capping layer 220 may improve the external luminous efficiency based on the principle of constructive interference.

The first capping layer 210 and the second capping layer 220 may be each independently a capping layer including an organic material, an inorganic capping layer including an inorganic material, or a composite capping layer including an organic material and an inorganic material.

At least one selected from the first capping layer 210 and the second capping layer 220 may include at least one material selected from carbocyclic compounds, heterocyclic compounds, amine-based compounds, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal-based complexes, and alkaline earth metal-based complexes. The carbocyclic compound, the heterocyclic compound, and the amine-based compound may each independently be optionally substituted with a substituent containing at least one element selected from O, N, S, selenium (Se), silicon (Si), fluorine (F), chlorine (CI), bromine (Br), and iodine (I). In one embodiment, at least one selected from the first capping layer 210 and the second capping layer 220 may include an amine-based compound.

In one embodiment, at least one selected from the first capping layer 210 and the second capping layer 220 may include the compound represented by Formula 201 or the compound represented by Formula 202.

In one or more embodiments, at least one selected from the first capping layer 210 and the second capping layer 220 may include a compound selected from Compounds HT28 to HT33 and Compounds CP1 to CP5, but is not limited thereto:

##STR00064##

Hereinbefore, the organic light-emitting device according to an embodiment has been described in connection with FIGS. 1-6. However, embodiments are not limited thereto.

The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a specific region using one or more suitable methods such vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and/or laser-induced thermal imaging (LITI).

When the layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region are each independently formed by vacuum deposition, the vacuum deposition may be performed at a deposition temperature of about 100 to about 500.degree. C., at a vacuum degree of about 10.sup.-8 to about 10.sup.-3 torr, and at a deposition rate of about 0.01 to about 100 .ANG./sec, depending on the compound to be included in each layer and the structure of each layer to be formed.

When the layers constituting the hole transport region, the emission layer, the and layers constituting the electron transport region are each independently formed by spin coating, the spin coating may be performed at a coating rate of about 2,000 revolutions per minute (rpm) to about 5,000 rpm and at a heat treatment temperature of about 80.degree. C. to 200.degree. C., depending on the compound to be included in each layer and the structure of each layer to be formed.

General Definition of Substituents

The term "C.sub.1-C.sub.60 alkyl group" as used herein may refer to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms. Non-limiting examples thereof may include a methyl group, an ethyl group, a propyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. The term "C.sub.1-C.sub.60 alkylene group" as used herein may refer to a divalent group having the same structure as the C.sub.1-C.sub.60 alkyl group.

The term "C.sub.2-C.sub.60 alkenyl group" as used herein may refer to a hydrocarbon group having at least one carbon-carbon double bond at one or more positions along the hydrocarbon chain of the C.sub.2-C.sub.60 alkyl group (e.g., in the middle and/or at either terminus of the C.sub.2-C.sub.60 alkyl group). Non-limiting examples thereof may include an ethenyl group, a propenyl group, and a butenyl group. The term "C.sub.2-C.sub.60 alkenylene group" as used herein may refer to a divalent group having the same structure as the C.sub.2-C.sub.60 alkenyl group.

The term "C.sub.2-C.sub.60 alkynyl group" as used herein may refer to a hydrocarbon group having at least one carbon-carbon triple bond at one or more positions along the hydrocarbon chain of the C.sub.2-C.sub.60 alkyl group (e.g., in the middle and/or at either terminus of the C.sub.2-C.sub.60 alkyl group). Non-limiting examples thereof may include an ethynyl group and a propynyl group. The term "C.sub.2-C.sub.60 alkynylene group" as used herein may refer to a divalent group having the same structure as the C.sub.2-C.sub.60 alkynyl group.

The term "C.sub.1-C.sub.60 alkoxy group" as used herein may refer to a monovalent group represented by --OA.sub.101 (where A.sub.101 is the C.sub.1-C.sub.60 alkyl group). Non-limiting examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.

The term "C.sub.3-C.sub.10 cycloalkyl group" as used herein may refer to a monovalent saturated hydrocarbon monocyclic group including 3 to 10 carbon atoms. Non-limiting examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term "C.sub.3-C.sub.10 cycloalkylene group" as used herein may refer to a divalent group having the same structure as the C.sub.3-C.sub.10 cycloalkyl group.

The term "C.sub.1-C.sub.10 heterocycloalkyl group" as used herein may refer to a monovalent monocyclic group including at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms. Non-limiting examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term "C.sub.1-C.sub.10 heterocycloalkylene group" as used herein may refer to a divalent group having the same structure as the C.sub.1-C.sub.10 heterocycloalkyl group.

The term "C.sub.3-C.sub.10 cycloalkenyl group" as used herein may refer to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one double bond in its ring, and is not aromatic. Non-limiting examples thereof may include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term "C.sub.3-C.sub.10 cycloalkenylene group" as used herein may refer to a divalent group having the same structure as the C.sub.3-C.sub.10 cycloalkenyl group.

The term "C.sub.1-C.sub.10 heterocycloalkenyl group" as used herein may refer to a monovalent monocyclic group including at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Non-limiting examples of the C.sub.1-C.sub.10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term "C.sub.1-C.sub.10 heterocycloalkylene group" as used herein may refer to a divalent group having the same structure as the C.sub.1-C.sub.10 heterocycloalkyl group.

The term "C.sub.6-C.sub.60 aryl group" as used herein may refer to an aromatic monovalent group having 6 to 60 carbon atoms. The term "C.sub.6-C.sub.60 arylene group" as used herein may refer to an aromatic divalent group having 6 to 60 carbon atoms. Non-limiting examples of the C.sub.6-C.sub.60 aryl group may include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C.sub.6-C.sub.60 aryl group and the C.sub.6-C.sub.60 arylene group each independently include a plurality of rings, the respective rings may be fused to each other.

The term "C.sub.1-C.sub.60 heteroaryl group" as used herein may refer to a monovalent group having a heterocyclic aromatic system that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom and 1 to 60 carbon atoms. The term "C.sub.1-C.sub.60 heteroarylene group" as used herein may refer to a divalent group having a heterocyclic aromatic system including at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom and 1 to 60 carbon atoms. Non-limiting examples of the C.sub.1-C.sub.60 heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C.sub.1-C.sub.60 heteroaryl group and the C.sub.1-C.sub.60 heteroarylene group each independently include a plurality of rings, the respective rings may be fused to each other.

The term "C.sub.6-C.sub.60 aryloxy group" as used herein may refer to a group represented by --OA.sub.102 (where A.sub.102 is the C.sub.6-C.sub.60 aryl group). The term "C.sub.6-C.sub.60 arylthio group" as used herein may refer to a group represented by --SA.sub.103 (where A.sub.103 is the C.sub.6-C.sub.60 aryl group).

The term "monovalent non-aromatic condensed polycyclic group" as used herein may refer to a monovalent group that has a plurality of rings condensed (e.g., fused) to each other, and has only carbon atoms (e.g., 8 to 60 carbon atoms) as ring forming atoms, wherein the molecular structure as a whole is non-aromatic (e.g., does not have overall aromaticity). A non-limiting example of the monovalent non-aromatic condensed polycyclic group may be a fluorenyl group. The term "divalent non-aromatic condensed polycyclic group" as used herein may refer to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

The term "monovalent non-aromatic condensed heteropolycyclic group" as used herein may refer to a monovalent group that has two or more rings condensed (e.g., fused) with each other, and has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, other than carbon atoms (e.g., 1 to 60 carbon atoms), wherein the molecular structure as a whole is non-aromatic (e.g., does not have overall aromaticity). A non-limiting example of the monovalent non-aromatic condensed heteropolycyclic group may be a carbazolyl group. The term "divalent non-aromatic condensed heteropolycyclic group" as used herein may refer to a divalent group having the same structure as the monovalent non-aromatic condensed hetero-polycyclic group.

The term "C.sub.5-C.sub.60 carbocyclic group" as used herein may refer to a monocyclic or polycyclic group having 5 to 60 carbon atoms only as ring-forming atoms. The term "C.sub.5-C.sub.60 carbocyclic group" as used herein may refer to an aromatic carbocyclic group or a non-aromatic carbocyclic group. The term "C.sub.5-C.sub.60 carbocyclic group" as used herein may refer to a ring (such as a benzene group), a monovalent group (such as a phenyl group), or a divalent group (such as a phenylene group). In one or more embodiments, depending on the number of substituents connected to the C.sub.5-C.sub.60 carbocyclic group, the C.sub.5-C.sub.60 carbocyclic group may be a trivalent group or a quadrivalent group.

The term "C.sub.1-C.sub.60 heterocyclic group" as used herein may refer to a group having the same structure as a C.sub.1-C.sub.60 carbocyclic group, except that as a ring-forming atom, at least one heteroatom selected from N, O, Si, P, and S is used in addition to carbon atoms (e.g., 1 to 60 carbon atoms).

In the present specification, at least one of substituents of the substituted C.sub.5-C.sub.60 group, substituted C.sub.1-C.sub.60 heterocyclic group, substituted C.sub.3-C.sub.10 cycloalkylene group, substituted C.sub.1-C.sub.10 heterocycloalkylene group, substituted C.sub.3-C.sub.1 cycloalkenylene group, substituted C.sub.1-C.sub.10 heterocycloalkenylene group, substituted C.sub.6-C.sub.60 group, substituted C.sub.1-C.sub.60 heteroarylene group, substituted divalent non-aromatic condensed polycyclic group, substituted divalent non-aromatic condensed heteropolycyclic group, substituted C.sub.1-C.sub.60 alkyl group, substituted C.sub.2-C.sub.60 alkenyl group, substituted C.sub.2-C.sub.60 alkynyl group, substituted C.sub.1-C.sub.60 alkoxy group, substituted C.sub.3-C.sub.10 cycloalkyl group, substituted C.sub.1-C.sub.10 heterocycloalkyl group, substituted C.sub.3-C.sub.10 cycloalkenyl group, substituted C.sub.1-C.sub.10 heterocycloalkenyl group, substituted C.sub.6-C.sub.60 aryl group, substituted C.sub.6-C.sub.60 aryloxy group, substituted C.sub.6-C.sub.60 arylthio group, substituted C.sub.1-C.sub.60 heteroaryl group, substituted monovalent non-aromatic condensed polycyclic group, and substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from the group consisting of:

deuterium(-D), --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 group, a C.sub.2-C.sub.60 alkynyl group, and a C.sub.1-C.sub.60 alkoxy group;

a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, and a C.sub.1-C.sub.60 alkoxy group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.11)(Q.sub.12)(Q.sub.13), --N(Q.sub.11)(Q.sub.12), --B(Q.sub.11)(Q.sub.12), --C(.dbd.O)(Q.sub.11), --S(.dbd.O).sub.2(Q.sub.11), and --P(.dbd.O)(Q.sub.11)(Q.sub.12);

a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, --Si(Q.sub.21)(Q.sub.22)(Q.sub.23), --N(Q.sub.21)(Q.sub.22), --B(Q.sub.21)(Q.sub.22), --C(.dbd.O)(Q.sub.21), --S(.dbd.O).sub.2(Q.sub.21), and --P(.dbd.O)(Q.sub.21)(Q.sub.22); and

--Si(Q.sub.31)(Q.sub.32)(Q.sub.33), --N(Q.sub.31)(Q.sub.32), --B(Q.sub.31)(Q.sub.32), --C(.dbd.O)(Q.sub.31), --S(.dbd.O).sub.2(Q.sub.31), and --P(.dbd.O)(Q.sub.31)(Q.sub.32),

wherein Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 may be each independently selected from hydrogen, deuterium, --F, --Cl, --Br, --I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group.

The term "Ph" as used herein may refer to a phenyl group. The term "Me" as used herein may refer to a methyl group. The term "Et" as used herein may refer to an ethyl group. The term "ter-Bu" or "Bu.sup.t" as used herein may refer to a tert-butyl group. The term "OMe" as used herein may refer to a methoxy group, and "D" may refer to deuterium.

The term "biphenyl group" as used herein may refer to a phenyl group substituted with a phenyl group. The "biphenyl group" may be a substituted phenyl group having a C.sub.6-C.sub.60 aryl group as a substituent.

The term "terphenyl group" as used herein may refer to a phenyl group substituted with a biphenyl group. The "terphenyl group" may be a substituted phenyl group having a C.sub.6-C.sub.60 aryl group substituted with a C.sub.6-C.sub.60 aryl group as a substituent.

The symbols * and *' as used herein, unless defined otherwise, refer to a binding site to an adjacent atom in a corresponding formula.

Hereinafter a compound and an organic light-emitting device according to one or more embodiments will be described in more detail with reference to Synthesis Examples and Examples. The expression "B was used instead of A" used in describing Synthesis Examples may refer to a molar equivalent of A being identical to a molar equivalent of B.

EXAMPLES

Example 1

As a substrate and an anode, a Corning 15 Ohms per square centimeter (.OMEGA./cm.sup.2) (150 .ANG.) ITO glass substrate was cut to a size of 50 millimeters (mm).times.50 mm.times.0.7 mm, sonicated by using isopropyl alcohol and deionized water for 5 minutes, respectively, and cleaned by exposure to ultraviolet rays with ozone. Then, the glass substrate was mounted on a vacuum deposition device.

TATC (100 .ANG.), HAT-CN (50 .ANG.), and NPB (100 .ANG.) were sequentially deposited on the ITO anode to form a hole transport region.

HTL1 (100 .ANG.) was deposited on the hole transport region to form a lower auxiliary layer, AND (ADN) and DPAVBi (the amount of DPAVBi was 5 percent by weight (wt %)) were co-deposited at a total thickness of 200 .ANG. to form an emission layer, and Alq (50 .ANG.) was deposited on the emission layer to form an upper auxiliary layer, to thereby form a first emission unit.

Compound 1 and Yb (the amount of Yb was 2 wt %) were co-deposited on the first emission unit at a total thickness of 150 .ANG. to form an n-type charge generating layer, and HAT-CN (100 .ANG.) was deposited on the n-type charge generating layer to form a p-type charge generating layer, to thereby form a first charge generating layer.

HTL1 (200 .ANG.) was deposited on the first charge generating layer to form a lower auxiliary layer, CBP and (BT).sub.2Ir(acac) (the amount of (BT).sub.2Ir(acac) was 15 wt %) were co-deposited on the lower auxiliary layer at a total thickness of 200 .ANG. to form an emission layer, and Alq (50 .ANG.) was deposited on the emission layer to form an upper auxiliary layer, to thereby form a second emission unit.

Compound 1 and Yb (the amount of Yb was 2 wt %) were co-deposited on the second emission unit at a total thickness of 150 .ANG. to form an n-type charge generating layer, and HAT-CN (100 .ANG.) was deposited on the n-type charge generating layer to form a p-type charge generating layer, to thereby form a second charge generating layer.

NPB (100 .ANG.) and HTL1 (100 .ANG.) were sequentially deposited on the second charge generating layer to form a lower auxiliary layer, and AND (ADN) and DPAVBi (the amount of DPAVBi was 5 wt %) were co-deposited on the lower auxiliary layer at a total thickness of 200 .ANG. to form an emission layer, to thereby form a third emission unit.

Alq (50 .ANG.) was deposited on the third emission unit to form a first electron transport layer, Compound 1 and Yb (the amount of Yb was 2 wt %) were co-deposited on the first electron transport layer at a total thickness of 200 .ANG. to form a second electron transport layer, and LiF (15 .ANG.) was deposited on the second electron transport layer to form an electron injection layer, to thereby form an electron transport region.

Al (100 .ANG.) was deposited on the electron transport region to form a cathode, thereby completing the manufacture of an organic light-emitting device.

Examples 2 and 3 and Comparative Example 1

Organic light-emitting devices were manufactured in the same (or substantially the same) manner as in Example 1, except that the materials shown in Table 1 were used in the n-type charge generating layer and in the second electron transport layer.

Evaluation Example 1

The driving voltage (V), efficiency (cd/A), and lifespan (T97) of the organic light-emitting devices manufactured in Examples 1 to 3 and Comparative Example 1 were measured by using Keithley source-measure unit (SMU) 236 and a luminance meter PR650. The results thereof are shown in Table 1.

TABLE-US-00001 TABLE 1 n-type charge n-type charge generating generating layer for the layer for the first charge second charge Second electron Driving generating layer generating l

Claims

What is claimed is:

1. An organic light emitting device comprising: a first electrode; a second electrode facing the first electrode; m emission units stacked between the first electrode and the second electrode; and m-1 charge generating layer(s) between each of the two adjacent emission units from among the m emission units, m-1 charge generating layer(s) comprising m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s), wherein m is an integer of 2 or greater, a maximum emission wavelength of light emitted from at least one of the m emission units differs from that of light emitted from at least one of the other emission units, at least one of the m-1 n-type charge generating layer(s) comprises a metal-containing material and an electron transporting metal-non-containing material, the metal-containing material comprised in the m-1 n-type charge generating layer(s) comprises a metal, a metal complex, or a combination thereof, the metal comprised in the m-1 n-type charge generating layer(s) comprises lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), or a combination thereof, and the metal complex comprised in the m-1 n-type charge generating layer(s) comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and at least one organic ligand selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxy benzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, and the organic light emitting device further comprises: an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units, wherein the electron transport layer comprises a metal-containing material and an electron transporting metal-non-containing material, the metal-containing material comprised in the electron transport layer comprises a metal, a metal complex, or a combination thereof, the metal comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the metal complex comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the electron transporting metal-non-containing material is an organic compound comprising at least one selected from a phenanthroline ring, an imidazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring, and the electron transporting metal-non-containing material comprised in the electron transport layer does not include the following compounds: ##STR00068## wherein the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer; the electron transporting metal-non-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer; or the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer, and the electron transporting metal-non-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer; and at least one of the m-1 n-type charge generating layer(s) and the electron transporting layer does not include a metal complex comprising lithium (Li).

2. The organic light-emitting device of claim 1, wherein when the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) comprises the metal, the metal is Yb.

3. The organic light-emitting device of claim 1, wherein when the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) comprises the metal complex, the metal complex comprises a metal selected from lithium (Li), aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), zinc (Zn), and copper (Cu).

4. The organic light-emitting device of claim 1, wherein when the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) comprises the metal complex, the metal complex is a Li complex and/or an Al complex.

5. The organic light-emitting device of claim 1, wherein when the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) comprises the metal complex, the metal complex is lithium quinolate (Liq) or aluminum quinolate (Alq3).

6. The organic light-emitting device of claim 1, wherein a lowest unoccupied molecular orbital (LUMO) energy level of the electron transporting metal-non-containing material is about -4.0 electron volts (eV) or greater.

7. The organic light-emitting device of claim 1, wherein the electron transporting metal-non-containing material is an organic compound comprising at least one .pi. electron-depleted nitrogen-containing ring.

8. The organic light-emitting device of claim 1, wherein when the metal-containing material comprises the metal, a weight ratio of the metal to the electron transporting metal-non-containing material is in a range of about 0.01:100 to about 15:100.

9. The organic light-emitting device of claim 1, wherein when the metal-containing material comprises the metal complex, a weight ratio of the metal complex to the electron transporting metal-non-containing material is in a range of about 1:100 to about 100:1.

10. The organic light-emitting device of claim 1, further comprising: a hole transport region between the first electrode and an emission unit adjacent to the first electrode from among the m emission units, and a p-dopant in the hole transport region, the LUMO energy level of the hole transport region being about -3.5 eV or less.

11. An organic light emitting device comprising: a first electrode; a second electrode facing the first electrode; m emission units stacked between the first electrode and the second electrode; and m-1 charge generating layer(s) between each of the two adjacent emission units from among the m emission units, m-1 charge generating layer(s) comprising m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s), wherein a maximum emission wavelength of light emitted from at least one of the m emission units differs from that of light emitted from at least one of the other emission units, at least one of the m-1 n-type charge generating layer(s) comprises a metal-containing material and an electron transporting metal-non-containing material, the metal-containing material comprised in the m-1 n-type charge generating layer(s) comprises a metal, a metal complex, or a combination thereof, the metal comprised in the m-1 n-type charge generating layer(s) comprises lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), or a combination thereof, and the metal complex comprised in the m-1 n-type charge generating layer(s) comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and at least one organic ligand selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxy benzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, and the organic light emitting device further comprises: an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units, wherein the electron transport layer comprises a metal-containing material and an electron transporting metal-non-containing material, the metal-containing material comprised in the electron transport layer comprises a metal, a metal complex, or a combination thereof, the metal comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the metal complex comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the electron transporting metal-non-containing material is an organic compound comprising at least one selected from a phenanthroline ring, an imidazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring, and the electron transporting metal-non-containing material comprised in the electron transport layer does not include the following compounds: ##STR00069## wherein m is an integer of 3 or greater, the m-1 n-type charge generating layer(s) all comprise the same metal-containing material and the same electron transporting metal-non-containing material, and the metal-containing material comprised in the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer; the electron transporting metal-non-containing material comprised in the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer; or the metal-containing material comprised in the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer, and the electron transporting metal-non-containing material comprised in the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer.

12. The organic light-emitting device of claim 1, wherein m is 2 or 3.

13. An organic light emitting device comprising: a first electrode; a second electrode facing the first electrode; m emission units stacked between the first electrode and the second electrode; and m-1 charge generating layer(s) between each of the two adjacent emission units from among the m emission units, m-1 charge generating layer(s) comprising m-1 n-type charge generating layer(s) and m-1 p-type charge generating layer(s), wherein m is an integer of 2 or greater, a maximum emission wavelength of light emitted from at least one of the m emission units differs from that of light emitted from at least one of the other emission units, at least one of the m-1 n-type charge generating layer(s) consists of a metal-containing material and an electron transporting metal-non-containing material the metal-containing material in the m-1 n-type charge generating layer(s) consists of a metal, a metal complex, or a combination thereof, the metal in the m-1 n-type charge generating layer(s) consists of lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), or a combination thereof, and the metal complex in the m-1 n-type charge generating layer(s) consists of an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, and at least one organic ligand selected from a hydroxyquinoline, a hydroxyisoquinoline, a hydroxy benzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyl oxazole, a hydroxyphenyl thiazole, a hydroxydiphenyl oxadiazole, a hydroxydiphenyl thiadiazole, a hydroxyphenyl pyridine, a hydroxyphenyl benzimidazole, a hydroxyphenyl benzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, and the organic light emitting device further comprises: an electron transport layer between the second electrode and an emission unit adjacent to the second electrode from among the m emission units, wherein the electron transport layer comprises a metal-containing material and an electron transporting metal-non-containing material, the metal-containing material comprised in the electron transport layer comprises a metal, a metal complex, or a combination thereof, the metal comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the metal complex comprised in the electron transport layer comprises an alkali metal, an alkaline earth metal, a rare-earth metal, a transition metal, a late transition metal, or a combination thereof, the electron transporting metal-non-containing material is an organic compound comprising at least one selected from a phenanthroline ring, an imidazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring, and the electron transporting metal-non-containing material comprised in the electron transport layer does not include the following compounds: ##STR00070## wherein the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer; the electron transporting metal-non-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer; or the metal-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the metal-containing material comprised in the electron transport layer, and the electron transporting metal-non-containing material comprised in the at least one of the m-1 n-type charge generating layer(s) differs from the electron transporting metal-non-containing material comprised in the electron transport layer; and at least one of the m-1 n-type charge generating layer(s) and the electron transporting layer does not include a metal complex comprising lithium (Li).

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